People are feeding wild birds for a variety of reasons including entertainment, relaxation, observing and/or studying nature, provide meaningful support to local populations, and so on. As stated above, many wild bird populations are declining. Reasons for the declines include habitat loss, environmental degradation, seasonal changes, local weather, climate change, inadequate forage, and so on. Wild birds have a relatively high metabolic rate that requires food on a regular and consistent basis. Many birds die during the winter, during droughts, cold spells, prolonged rains, and any other conditions that reduce the availability of forage leading to stress,weakness, reduced resistance to disease and parasites, and starvation. Feeding wild birds can help sustain populations when natural food supplies are hard to find.
Feeding Preferences of Wild Birds
Whether your goal is just to attract wild birds to a feeding station for your own enjoyment or to provide birds with the minimum nutrients they need for optimum health and reproduction, feeding preferences of birds are very important in determining what type of food products will best meet your needs.
In general, wild birds can be grouped together by the types of feed they eat. This does not necessarily mean that granivores (seed-eaters), for example, eat only seed. Granivores prefer seed to other foods and specific types of seed to others. Since it is rare in nature to find a food that is readily and always available, it is important to remember that most birds select food in order of their preferences.
While there are a number of types of feed, feeding wild birds usually involves only four:
a. Granivores - seed or grain feeders like finches and sparrows. Many seeds and seed mixes are available for
granivores.
b. Frugivores - fruit feeders like tanagers. There are dehydrated fruit products for frugivores.
c. Insectivores - insect feeders like blue birds and woodpeckers. There are a number of live and dehydrated
insect products.
d. Nectarivores - nectar feeders like hummingbirds. There are several commercial nectar diets available.
In addition to the importance of feeding preferences when feeding wild birds, feeding behaviors of wild birds should be considered when selecting feeders. Some wild birds including robins and doves forage on the ground. Others like woodpeckers and nuthatches forage on the bark of trees. Goldfinches and other granivores forage on the seed heads of grasses.
Casual Bird Feeding
The vast majority of people who are feeding wild birds are casual participants. For them feeding wild birds is primarily a part time activity involving offering wild birds treats and enjoying the benefits of watching their behaviors. The casual participant is one who may on impulse, while shopping at the supermarket, grab a bag of seed or a suet cake. They do not feel any responsibility for feeding wild birds anything more then bird candy. Wild birds are free to forage for their own nutritional needs. If your interest in feeding wild birds is casual, there is an entire industry devoted to meeting your needs. The primary function of the products offered is to bait or draw birds to a feeding site designed to provide maximum visibility for your viewing pleasure. All the feed products including seeds, seed mixes, suet products, and other specialty products are formulated for their ability to attract birds. Nutritional value is not a consideration. Seeds, seed mixes, and suet products offer at best incidental, supplemental nutrition. Even if it were possible to formulate a seed mix that met all the nutritional requirements of birds, it would fail because birds will preferentially select only the seeds they like, the most preferred being oil-type sunflower seed. Seed preference studies have demonstrated time after time that, oil-type sunflower seed, white proso millet, and Nyjer® are the preferred seeds of most species of birds that frequent feeders.
Seed Mixes
Seed mixes are best viewed as bird candy. The preferred seeds provide a burst of energy but little nutrition. Birds are like children, they eat what they like rather than what is nutritionally best for them.
In selecting seeds or seed mixes you should consider what seeds are in the mix. The cheaper the seed mix the higher the content of filler seeds like corn, milo, oats, wheat and others that the majority of birds find unpalatable. They usually end up on the ground under the feeding station. There is a growing trend in new housing communities to ban bird feeding because of the seed accumulation under the bird feeder and the pests that they attract. Another factor in the pricing of seeds and seed mixes is the grading of the seeds according to quality and any additional processing like cleaning or dehulling the seeds. Premium seed products are cleaner, contain the best grade of seeds, contain a larger proportion of the most palatable seeds like oil-type sunflower seed, and may be dehulled. The reality is that, with the exception of products that contain a higher percentage of the more palatable seeds, none of these added value, higher priced seed mixes make any difference to the birds. They are primarily for human market appeal. You are far better off buying the three individual seeds; oil-type sunflower seed, white proso millet, and Nyjer®. Even the millet is questionable as it attracts alien, invasive house sparrows which should be discouraged.
Bird feed should never be exposed to rain or direct sun both of which will cause deterioration in nutrients.
Suet
Wild bird suet products [http://www.aviancuisine.com/suet-vs-vegetable-fat] are available in a variety of shapes and formulations. The shapes typically include the standard cake, plugs, balls or "berries", bells, and so on. In addition to plain suet, formulations consist of suet incorporating small amounts of attractants like, berries, fruit, insects, nuts, and seeds to appeal to different wild bird species. While the attractants have a small influence on the kind of wild birds that are attracted to a particular suet product, their real impact is in appealing to human consumers . The primary nutritional component in wild bird suet products is beef fat. It provides energy, which is vital to wild birds. Suet cakes and other suet products attract bark-climbing wild bird species like woodpeckers, nuthatches, and so on. Wild bird suet cakes, like seed and seed mixes may improve survivor rates in the short term and they are very economical. In selecting suet products, the consumer should look for the softest products that will meet the conditions at their feeding station. Softness indicates a relatively low melting temperature. The lower the melting temperature, the easier the product is for wild birds to digest.
Over the past five to ten years there has been a trend among suet processors to develop wild bird suet products with increasingly higher melting temperatures. This is just another marketing scheme that is designed to appeal to human consumers at the expense of the best interests of birds. Do not be fooled. It is in the best interest of wild birds to consume fats that contain the least amount of saturated fats and triglycerides. Wild birds are attracted to fat because of its high energy content. However, birds must expend energy, not only to access and consume fats, but to digest them. The melting temperature of a fat is directly related to its degree of saturation. The higher the saturation, the higher the melting temperature, the more energy necessary to digest it.